Details

Autor(en) / Beteiligte

• Berber-Mendoza, Maria Selene
• Leyva-Ramos, Roberto
• Alonso-Davila, Pedro
• Mendoza-Barron, Jovita
• Diaz-Flores, Paola Elizabeth

Titel

Effect of pH and temperature on the ion-exchange isotherm of Cd(II) and Pb(II) on clinoptilolite

Ist Teil von

• Journal of chemical technology and biotechnology (1986), 2006-06, Vol.81 (6), p.966-973

Ort / Verlag

Chichester, UK: John Wiley & Sons, Ltd

Erscheinungsjahr

2006

Quelle

Wiley-Blackwell Journals

Beschreibungen/Notizen

• The ion‐exchange equilibrium of Pb(II) and Cd(II) on clinoptilolite from different deposits was studied in this work. The Langmuir isotherm fitted the ion‐exchange equilibrium data of both ions better than the Freundlich isotherm. The capacity of the natural zeolite to exchange Cd(II) and Pb(II) increased, augmenting the solution pH. This behaviour was attributed to the interactions between the ions in solution and the surface charge of the zeolite. Moreover, the capacity of the natural zeolite to exchange Cd(II) and Pb(II) was increased when the temperature was raised from 15 to 35 °C. This tendency was explained by assuming that the ion exchange was an endothermic reaction. The selectivity of the zeolite for the metal cations decreased in the following order: Pb(II) > Cd(II). This order was not modified while reducing the solution pH, but the zeolite selectivity was increased. At pH 2 the selectivity of the zeolite for Pb(II) was nearly three times larger than at pH 4. Copyright © 2006 Society of Chemical Industry